Rheem RTGH Owners Manual

35
INSTALLATION INSTRUCTIONS
Venting
Vent Lengths and
DIPswitch Adjustments
Before starting the vent installation, careful planning
should be given to the routing and termination of the
vent pipes. The length of the vent pipes (inlet and
outlet) should be kept to a minimum. Also, see pages
39–40 and 46 for vent terminal placement. Refer to the
maximum and minimum vent length charts for the pipe
sizes that can be used and the total equivalent length
of pipe that can be used. DO NOT exceed equivalent
length of pipe in maximum vent length chart.
Appropriate dip switch adjustment shall be required to
allow certain vent length. There are 2 vent configuration
settings, A-1 and A-2 settings at 0 - 2,000 ft (0 - 610 m)
elevation.
A-1 setting is default and factory setting. All dip switches
are off.
Minimum Vent Length (intake/outlet):
Number of
90° Elbows
Minimum Length
of 2" or 3" Straight
Pipe
1 1.0 ft. (0.3 m)
Maximum Vent Length (intake/outlet)
Number of
90° Elbows
Maximum Length of 2"
Straight Pipe
Maximum Length of 3"
Straight Pipe
1 22.0 ft (6.7 m) 148.5 ft (45.3 m)
2 19.0 ft (5.8 m) 147.0 ft (44.8 m)
3 16.0 ft (4.9 m) 145.5 ft (44.3 m)
4 13.0 ft (4.0 m) 144.0 ft (43.9 m)
5 10.0 ft (3.0 m) 142.5 ft (43.4 m)
6 7.0 ft (2.1 m) 141.0 ft (43.0 m)
To have a longer vent length with 2" vent, A-2 setting is
required:
Turn off the gas and water to the water heater by closing
the shut-off valves.
Remove the front cover panel on the water heater.
Find DIP Switch 2 located in the top-right portion of the
control board. The switch labeled “DIP 2” is the bottom
switch.
The factory settings for this switch should all be in the
OFF position (DOWN).
Venting for Direct-Vent Water Heater
As set
from factory
MIN MAX ADJ
1
Control
Board
Dip Switches
3
2
4
As set
from factory
MIN MAX ADJ